Search Results (46)

The aim of this study was to explore the effects of different lactic acid bacteria additives (Lactiplantibacillus plantarum or Lentilactobacillus buchneri) on the fermentation quality, chemical composition, in vitro digestibility, bacterial community structure, and predictive function of S. perfoliatum silage feed. Fresh S. perfoliatum was wilted overnight, then its moisture content was adjusted between 65 and 70%. The experiment was performed in three groups as follows: (1) the control group (CK group), which lacked a Lactobacillus preparation; (2) the Lactiplantibacillus plantarum (L. plantarum) group (LP group), which was inoculated with L. plantarum at 5 × 10⁶ cfu/g FW; and (3) the Lentilactobacillus buchneri (L. buchneri) group (LB group), which was inoculated with L. buchneri at 5 × 10⁶ cfu/g FW. The results showed that L. plantarum significantly reduced pH and increased lactic acid (LA) content in S. perfoliatum silage compared with the control. L. buchneri, on the other hand, excelled in reducing ammonia nitrogen (NH₃-N) content and significantly increased acetic acid (AA) content. At 60 days of fermentation, the CP content was significantly higher (p < 0.05) in the LP and LB groups than in the CK group (19.29 vs. 15.53 and 15.87). At 60 days of fermentation, the ivCPD was significantly higher (p < 0.05) in the LB group than in the CK and LP groups (57.80 vs. 54.77 and 55.77). The 60-day silage process completely altered the bacterial community of S. perfoliatum silage. In the fresh samples, the dominant genera were Weissella_A and Pantoea_A. Weissella_A and Pantoea_A were gradually replaced by Lentilactobacillus and Lactiplantibacillus after S. perfoliatum ensiling. After 45 days of fermentation, L. buchneri became the dominant strain in CK, LP and LB groups. Inoculation with L. plantarum altered the succession of the bacterial community from 7 to 15 days of fermentation of S. perfoliatum. In contrast, inoculation with L. buchneri affected the succession of the bacterial community from 30 to 60 days of S. perfoliatum fermentation. In S. perfoliatum silage aged 7 to 60 days, the amino acid metabolic pathway in the LB group remained upregulated. The experimental results revealed that inoculation with L. buchneri had a stronger effect on S. perfoliatum silage than inoculation with L. plantarum. Thus, L. buchneri should be selected as an additive for S. perfoliatum silage fermentation in practical production. Full article

As a typical agricultural waste, the resource utilization of corn stover (CS) plays a crucial role in the coordinated optimization of ecological and economic benefits. In order to enhance the utilization of CS resources, Lentilactobacillus (L.) buchneri (LB) and different proportions of Artemisia argyi (AA) were added to CS to investigate the impact of additives on the fermentation quality and aerobic stability of corn stover silage (CSS). This study revealed that the separate addition of AA or LB in CS effectively improved the silage quality and aerobic stability. Specifically, LB exhibited the lowest pH value of 3.72 at 90 d of fermentation, while the NH₃-N content was 0.07 g/kg DM during the anaerobic fermentation stage and 0.19 g/kg DM during the aerobic exposure stage (p < 0.05). Mixing 30% AA increased the lactic acid content, lowered the pH, maintained a higher relative abundance of Lactobacillus, and reduced mycotoxin levels. In terms of aerobic stability, all AA-treated groups demonstrated superior performance compared to the LB treatment. Additionally, it was observed, that in the 30% AA group, Candida exhibited the highest relative abundance. Importantly, the addition of AA upregulated carbohydrate metabolism and lipid metabolism during the ensiling process, and their relative abundances remained high during aerobic exposure. Fully utilizing CS resources as feed to provide fiber and nutrients for ruminants can not only reduce the pressure on forage demand but meet the development needs of “grain-saving” animal husbandry, which is conducive to solving the contradictions of “human–animal competition for food” and “human animal competition for land”. Full article

Solid-state fermentation (SSF) is increasingly applied to enhance the functional properties of traditional herbal medicines. In this study, we investigated the effect of lactic acid bacteria (LAB) and other probiotic strains on the bioactive profile of Radix Angelica gigas (Danggui) during SSF. SSF was carried out by incubating a mixture of the herbal powder and distilled water (1:1, pH 7.0) with LAB strains (Lactobacillus rhamnosus, L. acidophilus, L. buchneri, L. reuteri, L. plantarum) and additional microbes (Bacillus subtilis, Saccharomyces cerevisiae) under controlled conditions. The 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities and total phenolic and flavonoid contents were measured. L. buchneri exhibited the highest growth, with significant proliferation observed on days 4 and 6, especially at 30 °C (p < 0.05). The DPPH and ABTS radical scavenging activities and total phenol and total flavonoid contents were increased by up to 230% (35 °C), 111% (30 °C), 137% (30 °C and 35 °C), and 133% (35 °C), respectively, in fermented herbs compared with those in non-fermented herbs. Antioxidant levels (DPPH, phenol, and flavonoid) exhibited a significant positive correlation with bacterial growth and a significant negative correlation with pH in SSF, but ABTS did not exhibit any statistically significant correlation with bacterial growth or pH. Moreover, multi-strain fermentations involving L. acidophilus and L. plantarum significantly increased the antioxidant activities compared to single-strain fermentations (p < 0.05). These findings suggest that SSF using probiotic LAB can significantly improve the bioactive composition of Radix Angelica gigas, providing a scientific method for modernizing traditional herbal medicine with potential uses in human and animal health. Full article

This study aimed to provide deeper insights into fermentation dynamics, aerobic stability, and bacterial community composition during the short-term ensiling of maize forage with lactic acid bacteria-based inoculants. A 50:50 combination of Lentilactobacillus buchneri DSM2250 and Lactococcus lactis DSM11037 (LBL target application: 150,000 CFU per 1 g forage) was tested alongside an untreated control (C) over fermentation periods of 2, 4, 8, 16, and 32 days. A total of 50 3 L mini-silos were filled with 2 kg of fresh maize each and stored at 20 °C. The pH, dry matter, nutrient profiles, volatile fatty acids, lactic acid, alcohols, ammonia-N, microbiological counts (yeast and mold), and aerobic stability of all samples were analyzed after seven days of air exposure. LBL silage showed higher average dry matter content (DMc) and crude protein (CP) levels by 1.5%, p < 0.001, and 10.8%, p < 0.001, respectively, as well as reduced average dry matter (DM) losses by half (p < 0.001) compared to pure silage. The beneficial effects of inoculation became more pronounced with prolonged storage, particularly by day 32 of fermentation. LBL silage showed increased production of lactic and acetic acids by an average of 55.5% and 5.0%, respectively, (p < 0.01) and significantly reduced butyric acid formation by approximately 14 times. Ethanol and ammonia-N concentrations were also reduced by 55.4% and 25.6%, respectively (p < 0.001), while the pH value remained 0.17 units lower (p < 0.001) compared to the control. The combination of the two strains improved silage aerobic stability by 2.4 days (p < 0.001) and extended shelf life by reducing yeast counts (8.02 vs. 7.35 log₁₀CFU g⁻¹ FM, p < 0.001), while maintaining the pH value close to its initial level. Therefore, compared to the untreated control, the inoculated silage exhibited higher nutritional value, reduced fermentation losses, and suppressed undesirable microbial activity. The positive effects of inoculation became increasingly evident over time, particularly by day 32, highlighting the synergistic benefits of using mixed-strain lactic acid bacteria. These findings support the use of LBL inoculants as an effective strategy to enhance short-term silage quality and stability. Full article

Additives are intentionally added to silage to reduce the growth of undesirable micro-organisms and to control the course of fermentation. This study aimed to evaluate the effect of two additives, a commercial product based on organic acids (OA) and Lentilactobacillus buchneri (Lb), alone or in combination with OA. The experiment was conducted in a 4 × 3 factorial completely randomized design, with five replicates per treatment, four additives (control, no additive (Control); commercial inoculant based on L. buchneri (Lb); additive based on organic acids (OA); Lb combined with OA (Blend)), and three fermentation periods (15, 30, and 90 days). The filamentous fungi count was higher in the Control silage during all fermentation periods. Lb silage showed greater aerobic stability (144 h) during all fermentation periods. The fermentation pattern was also influenced by inoculation; Lactobacillus was the most prevalent genus in Blend silage, and Lactiplantibacillus, Lacticaseibacillus, and Secundilactobacillus were predominant in OA silage, followed by Lentilactobacillus, which was higher in Lb silage. The addition of Lb and the Blend silage were the most efficient strategies, promoting greater accumulation of acetic acid and inhibiting yeasts, and the additives contributed to a more stable environment over 90 days of storage. Full article

The unique geographical environment of karst regions provides pickles with a favorable flavor and taste; however, the contribution of the microbial community to pickle fermentation has not been fully explored. In this study, high-throughput sequencing and untargeted metabolomics were used to characterize 60 naturally fermented pickle samples from 12 different karst regions. The bacterial communities and metabolites of naturally fermented pickles changed significantly between different karst regions. Lactobacillus delbrueckii, L. homohiochii, and L. fermentum were the dominant bacterial species in pickle samples, with relative abundances of 29.66, 8.05, and 7.12%, respectively. There exist significant variations in the core biomarkers of traditional pickles across diverse regions characterized by rocky desertification and varying temperatures. Both L. homohiochii and L. buchneri stimulated complicated interspecies interactions in the bacterial community. Lactobacillus species exhibit excellent inhibitory effects against harmful bacterial populations under E-low- and E-high-temperature conditions. In total, 1976 metabolites were identified in pickles, including many previously undiscovered metabolites (e.g., Citrulline, GABA, tyrosol, and L-hydroxyroline) attributable to the dominances of L. homohiochii, L. brevis, L. buchneri, and L. plantarum. Lower levels of biogenic amines were found in pickles from the low-temperature regions. Furthermore, L. delbrueckii and L. fermentum were significantly negatively (p < 0.05) correlated with spermine and tyramine, and Weissella cibaria was negatively (p < 0.05) correlated with histamine. These data indicated that a low-temperature environment may be beneficial to the fermentation of pickles. This work provides new insights into the flavor of pickles resulting from the geological distribution of bacterial flora in karst regions. Full article

Guanine deaminase (GDA) catalyzes the first step in purine catabolism by converting guanine to xanthine. Despite its significant role in the development of low-purine food, studies on GDA remain limited compared to other metabolic deaminases. To identify a GDA with high enzyme activity and appropriate optimum parameters, GDAs from Kluyveromyces lactis, Kluyveromyces marxianus, Lentilactobacillus kefiri, and Lactobacillus buchneri were heterologously expressed in Escherichia coli. The GDA from Kluyveromyces marxianus (KM-GD) showed the most potent enzyme activity (2.21 IU/mL) at 30 °C and pH 6.5, which is close to the pH of saccharified wort. Furthermore, analyzing the crystal structures of GDAs from different sources revealed that hydrogen bonds could enhance substrate affinity and strengthen enzyme activity. In addition, active pockets with an appropriate size may contribute to high enzyme activity. Finally, KM-GD helped reduce guanine by 80.33% in beer wort and by 80.00% in matured beer, thus suggesting its promise for industrial application in low-purine food production. Full article

This investigation aimed to assess the effect of additives on the aerobic stability, fermentation profile, and chemical composition of high-moisture corn grain silage. The corn grain was milled and divided this into four distinct treatment groups: Lentilactobacillus buchneri, propionic acid, Lactiplantibacillus plantarum, and no additive (control). The capacity of the silos was 1 L and density was 1000 kg/m³. Each group had three replicates and was fermented for 45 d. At silo opening, one part of silage was used for fermentation parameters, chemical composition, and in vitro dry matter digestibility analysis; another part was used for aerobic stability determination. Compared with the control, all additives increased lactic acid and dry matter concentrations (p < 0.001) and decreased neutral detergent fiber level (p < 0.001). In comparison with the control, the application of Lentilactobacillus buchneri and propionic acid improved silage aerobic stability, showed by lower pH level and yeast and mold populations after exposure to air. The findings offer theoretical groundwork and technological backing for the use of high-moisture corn grain silage. Full article

Clostridial fermentation is the determining process causing the spoilage of direct-cut alfalfa silage, and the application of lactic acid bacteria (LAB) inoculant is considered as the most promising technology for inhibiting clostridial fermentation. In order to screen target-based LAB strains, identification and correlation analysis of key Clostridia and LAB species in alfalfa silage were conducted in this study. Three alfalfa cultivars (Sanditi, SD; Celsius, CE; SW5909, SW) were harvested at the early bloom stage and ensiled without (CK) or with LAB inoculant (LB) and sucrose (SC) for 60 d. Single-molecule real-time sequencing was used to identify dominant Clostridia and LAB species, and LAB with significant inhibitory effects on dominant Clostridia was screened via correlation network analysis. The results showed that silages CK and LB encountered severe clostridial fermentation as indicated by large amounts of butyric acid (BA) and ammoniacal nitrogen (NH₃-N) production. Compared to silages CK and LB, SC treatment decreased (p < 0.05) BA and NH₃-N concentrations, as well as decreasing (p < 0.05) the bacterial community indexes of Shannon and Chao1. Lactiplantibacillus pentosus was the first dominant LAB in silage CK of alfalfa SD and CE. The first dominant LAB in silage LB was also identified as L. pentosus, rather than Lentilactobacillus buchneri and Lactiplantibacillus plantarum in the used inoculant. L. buchneri became more abundant in silage SC of alfalfa SD and CE, accounting for the high fermentation quality of these silages. Clostridium tyrobutyricum, Clostridium luticellarii, Garciella sp._GK3, Clostridium sporogenes, Clostridium perfringens, and Clostridium sp._BTY5 were the most dominant Clostridia species in alfalfa silage. Furthermore, Enterococcus faecalis, L. buchneri, and L. pentosus exhibited significant (p < 0.05) inhibitory effects on C. tyrobutyricum, C. luticellarii, and Garciella sp._GK3, respectively, which were the top three Clostridia species associated with clostridial fermentation. In conclusion, E. faecalis, L. buchneri, and L. pentosus were screened and can be used as potential LAB inoculants for the targeted inhibition of clostridial fermentation. Full article

This study aimed to evaluate the effects of wilting and exogenous lactic acid bacteria treatments on the chemical composition, fermentation quality, and microbial community composition of Plantago lanceolata silage (PS). This experiment was carried out in the Guizhou Extension Station of Grassland Technology (25°38′48″ N, 106°13′6″ E). The PS samples were divided into four treatment groups, namely control PS (C-PS), wilting-treated PS (W-PS), Lactobacillus brucei-treated PS (LB-PS), and wilting + L. brucei-treated PS (WLB-PS) groups, and analyzed after 60 d of treatment. The W-PS and WLB-PS groups showed significantly lower ether extract, ash, and Neutral detergent fiber contents but significantly higher water-soluble carbohydrate content compared to the C-PS and LB-PS groups (p < 0.05). Additionally, the W-PS group had significantly lower propionic acid content but significantly higher butyric acid content compared to the other groups (p < 0.05). Meanwhile, the WLB-PS group had the highest lactic acid content, the lowest pH, and no butyric acid content (p < 0.05). Additionally, the WLB-PS group showed a high proliferation of beneficial bacterial species (Lactobacillus buchneri and Lactobacillus plantarum) and decreased proliferation of undesirable bacterial species (Clostridium lutlcellarli and Clostridium tyrobutyricum). In conclusion, the combination treatment with wilting and L. brucei increased beneficial microorganisms and inhibited undesirable microorganisms during ensiling, thereby improving the fermentation quality of PS. Therefore, the combination treatment with wilting and L. brucei may be an effective Plantago lanceolata silage modulation technique. Full article

Despite efforts to prevent atypical ensiling conditions, such as delayed ensiling or sealing, these issues frequently occur in practice. This study aimed to investigate the effects of delayed ensiling (forage held for 24 h) and sealing, along with inoculation using a blend of Lentilactobacillus buchneri and Lactococcus lactis, on the characteristics of the resulting silages. Whole-plant maize (Zea mays L.) was treated with or without a commercial inoculant and ensiled (36% dry matter) for 60 days in 3.0 L glass containers. The forage was either ensiled immediately or subjected to a 24 h delay before ensiling. During the delay, the forage was either covered or left uncovered. Each treatment was replicated five times. All data were analyzed using the MIXED procedure of SAS statistical software (version 9.4; SAS Institute Inc., Cary, NC, USA). Delaying the ensiling process by 24 h worsens fermentation parameters, significantly increases dry matter (DM) losses (p < 0.01), and significantly reduces aerobic stability and the hygienic quality of the silage (p < 0.01), as evidenced by higher concentrations of undesirable fermentation products and elevated yeast and mold counts. The inoculation has a significant impact on both forage before ensiling and the characteristics of the resulting silage. Maize forage treated with inoculant showed a lower temperature increase by 8.2–8.1 °C (p < 0.01) when delayed for 24 h before ensiling. In silages, it also resulted in a reduced pH (p < 0.01); increased concentrations of lactic acid; acetic acid; and 1,2-propanediol (p < 0.01); and decreased levels of negative fermentation indicators such as ammonia-N, alcohols, and butyric acid (p < 0.01) During both the fermentation and aerobic exposure periods, inoculated silages exhibited up to 36% and 2.6 times lower (p < 0.01) dry matter loss, while suppressing the growth of yeasts and molds by up to 2.6 and 3.1 times (p < 0.01), respectively, compared to non-inoculated silages. The results of this study support the recommendation to minimize the duration of aerobic exposure of fresh forage during silo filling and to use LAB-based inoculants. Full article

Lactic acid bacteria (LAB) inoculants are commonly used in silage production, yet their effects on silage containing antimicrobial components, such as those found in Leonurus japonicus, remain less explored. Herein, the harvested alfalfa were thoroughly mixed with dried Leonurus japonicus Houtt. (LJH) at a ratio of 9:1 on a fresh weight basis and treated without (CK) or with a lactic acid bacterial inoculant (L; Lentilactobacillus buchneri). The mixtures were stored under anaerobic conditions in vacuum-sealed polyethylene bags for 30 days at ambient temperature. The L-treated silage exhibited high levels of water-soluble carbohydrates (4.98% dry matter (DM)) and acid detergent fiber (27.88% DM). Compared to that of treatment CK, treatment with L increased the acetic acid content of the silage, as a result of increased (p < 0.05) bacterial dominance and decreased (p < 0.05) bacterial richness indices (e.g., Pielou’s E, Shannon, and Simpson) in the pre-storage period. However, these changes gradually reduced as the storage length increased. Treatment L reshaped the bacterial community structure of silage, by increasing the prevalence of Lactobacillus and reducing relative abundances of Enterococcus and Weissella. However, the principal coordinate and Bray–Curtis index analyses illustrated that samples from the L-treated silages exhibited similarities to the CK samples post-fermentation. Overall, the effect of LJH on LAB was only observed in the later stages of fermentation, which did not sufficiently change the silage quality. Hence, using LJH in silage is vital for clean livestock production without compromising the function of LAB when mixed with alfalfa silage. Full article

In this experiment, Lactobacillus plantarum and Lactobacillus buchneri were added individually or in combination to Silphium perfoliatum L. (SP) silage to investigate the effects of different fermentation types of lactobacilli on the fermentation quality, in vitro digestibility, and aerobic stability of SP-silage, with a view to providing a certain scientific basis and technical support for obtaining high-quality SP-silage in production. The experiment comprised a non-additive group (control), an L. plantarum group (LP), an L. buchneri group (LB), and an L. plantarum and L. buchneri mixed treatment group (LPLB). Samples were taken after 60 days of fermentation and analyzed for the fermentation quality, in vitro digestibility, and aerobic stability of the SP-silage. The results showed that the addition of LP, LB, and LPLB significantly reduced the pH and proportion of ammonia nitrogen to total nitrogen and significantly increased the lactic acid, in vitro dry matter digestibility, and in vitro crude protein digestibility in the SP-silage (p < 0.05). Compared to the control group, the dry matter and crude protein contents of the LB and LPLB groups were significantly increased, while the neutral detergent fiber and acid detergent fiber contents were significantly reduced (p < 0.05). The SP-silage supplemented with LPLB had the highest dry matter and crude protein contents. The gross and digestible energies of the SP-silage in the LB and LPLB groups were significantly higher than those in the control and LP groups (p < 0.05). The aerobic stability of the SP-silage was significantly reduced by 24.14% in the LP group and increased by 58.62% and 34.48% in the LB and LPLB groups, respectively, compared to the control group (p < 0.05). It was shown that adding a combination of LP and LB resulted in the best fermentation quality, nutritional value, and in vitro digestibility of the SP-silage. LB was effective in improving the aerobic stability of SP-silage. Full article

This work aimed to assess microbial inoculants (Lactiplantibacillus plantarum and Lentilactobacillus buchneri), chemical additives (natamycin and hexanoic acid), and their combination on fermentation characteristics and aerobic stability in total mixed ration (TMR) silage. The TMR consisted of 30% water bamboo shell (WBS), 10% alfalfa, 20% rice straw, and 40% concentrate. There were six treatments as follows: (1) deionized water (control, CON). (2) lactic acid bacteria (Lactiplantibacillus plantarum + Lentilactobacillus buchneri; LPB, 1 × 10⁶ cfu/g FW). (3) natamycin (NT, 0.02 g/kg FW). (4) hexanoic acid (HA, 0.02 g/kg FW). (5) lactic acid bacteria + natamycin (SLNT, 0.02 g/kg FW). (6) lactic acid bacteria + hexanoic acid (SLHA, 0.02 g/kg FW). After fermentation, laboratory silos (10 L) were opened to assess fermentation quality, followed by a 6-day aerobic stability test. The results showed that all silages were well fermented with high lactic acid (LA) content, low ammonia nitrogen (NH₃-N), and negligible butyric acid (BA) levels. Among all silages, SLNT silage exhibited the greatest LA, acetic acid (AA) levels, LAB counts, and the lowest pH and NH₃-N. For aerobic stability, all additives significantly (p < 0.05) enhanced aerobic stability, delayed (p < 0.05) the decrease in LA and water-soluble carbohydrates (WSC) and the increase in pH, and significantly (p < 0.05) minimized yeast proliferation. The SLNT silage showed the best aerobic stability, with SLHA, NT, HA, and LPB following. In conclusion, SLNT is recommended as the optimal additive in improving the fermentation quality and aerobic stability of TMR silage, with SLHA, NT, HA, and LPB following. Full article

Whole crop corn silage (WCCS) been an important source of roughage for confined ruminants. However, at the silage feed-out phase, the rise in temperature and relative humidity under aerobic conditions breeds the production of undesirable microorganisms, such as yeast and mold. In order to investigate the conservation characteristics and aerobic stability underlying the effects of additives in whole crop corn silage (WCCS), whole crop corn (WCC) at the milk-ripe stage was ensiled with Lentilactobacillus (L.) buchneri (LB) and different proportions of Artemisia argyi (AA) for 90 days (d) at room temperature, respectively, and aerobic exposure after 90 d fermentation was also conducted. The study found that AA as an additive improved the fermentation quality and enhanced aerobic stability of WCCS, for which the addition of 60% AA increased the lactic acid fermentation rate, with the lactic acid concentration at the end of aerobic exposure significantly higher than in all other treatment groups, at 98.21 g/kg DM (p < 0.01), which decreased the relative abundance of none wanted microorganisms and reduced the content of fungal toxins (p < 0.05). After 90 d of fermentation, LB also increased the organic acids and reduced the pH compared with control, thereby improving fermentation quality. Furthermore, we also discovered that the relative abundance of Candida within the 60% AA was the highest. Candida have the ability to convert WSC into organic acids and lower pH, thus improving the quality of silage. Particularly, 60% AA could improve the fermentation quality and aerobic stability of silage through the biosynthetic pathways of phenylalanine, tyrosine and tryptophan, as well as by participation in the hydrolysis of glycoside hydrolases (GHs). Unexpectedly, the addition of AA was found to reduce the relative abundance of antibiotic resistance genes. WCC, ensiled with 60% AA, exhibited excellent fermentation quality and aerobic stability, providing a theoretical basis for understanding the mechanisms of AA which improve the quality of WCCS during the aeration phase. Full article